Sony BVH-2000, Operation And Maintenance Manual

Page: 278 / 505

5-3-5. AE-03
Board
board
nlavhack
and and the driver as
well as the time code recording and playback amplifiers. The
PS-04 model is also provided with the AUDIO-4 channel
circuitry.
Refer to AUDIO-3 SIGNAL SYSTEM in section A for a block
diagram of the AE-03 board. Refer to AUDIO-3 & AUDIO-4
SIGNAL
in section the block of the
the
Recording
The circuitry configuring the AUDIO-3/4 recording amplifier is
the same as that for the AUDIO-I/2 recording amplifier on the
AU board. With any model other than the PS-04, the crosstalk
generated between AUDIO-3 and CTL is cancelled out; with the
model, the crosstalk between AUDIO-3 AUDIO-4 is
recording
amplifier.
3.
Playback Amplifier
to 25
the A3 switch on the board is set the time
code signals can be played back. In order to read out the time
code signals from the
111 Ox speed to the maximum speed, the
switcher IC3 is switched by the NORMAL FWD+ EE signal
from the LG board; with the 1x normal speed, the signals which
have passed
through the filter are output as the playback
while any other the signals to passing
the output
VTR is switched
mode the mode
muting signal (A3 MUTE) is supplied to the 31A at a timmg
delayed by 8msec from the A3 TAPE/EE signal which is
supplied to the 30A pin.
Ql is a bias trap which is set on during l x speed to reduce the
bias leak (198.9 kHz).
BVH-2000( U/C)/PS/PM
BVH-2180(U/C)/PS/PM
the on same
board.
5. Meter Amplifier
The circuitry is the same as that of the AUDIO-I/2 on the AU
board.
Since the AUDIO-3 track and CTL track are close to each other,
crosstalk arises between the two tracks. Depending on the VTR
mode, this crosstalk is reduced by three types of cancellers.
(1) PB Mode (PB CTL to PB AUD-3)
Part of the PB CTL signal of the AP board is supplied to
the playback amplifier AE board
crosstalk.
In
CTL channels
REC
signal, produced by the CD board, is supplied
the AUDIO-3 playback amplifier to reduce the crosstalk.
(3) AUD-3 INSERT Mode (REC AUD-3 to PB CTL)
This canceller functions in the AUDIO-3 insert mode to
prevent the servo lock from being disengaged and the PB
CTL being disturbed by the effects of AUDIO-3.
AUDIO SIGNAL SYSTEM
z
o
~
<
a:
w
0...
o
>-
a:
o
w
I
f-
LO